DeCSS

The logical integrated circuits relate to the integrated circuits operative Numérique in logical Booléenne also called logic repeating spring (TOR).

Characteristics

The characteristics of the logical integrated circuits are standardized by letters:

I (Input) indicates an entry,
O (Output) an exit,
H (high) indicates the high state of an exit,
L (low) indicates the low state of an exit,
Z , HZ or X indicates the state high impedance of an exit 3 states.

Power supply of the case

The beach of food depends on technology used. It is generally of 5V for the old components (TTL), and of 3,3V, 2,5V even less for recent technologies (CMOS, LV-CMOS…).

Consumption

The consumed electric output depends on technology used (smoothness of the engraving of silicon), and increases linearly with the Fréquence and with the square of the supply voltage.

This is why the most recent technologies use increasingly weak supply voltages to be able to increase the frequency of operation without risking the destruction by heating.

Sizes of input-output

Tensions

Tension of entry high level

V_IH is the necessary tension to be regarded as a logical 1 in entry. A lower tension is likely to be badly interpreted by the stage of entry.

Tension of entry bottom grade

V_IL is the necessary tension to be regarded as a 0 logical in entry. A higher tension is likely to be badly interpreted by the stage of entry.

Output voltage high level

V_OH is the power provided to be regarded as a logical 1 at exit. The minimal value is indicated by the manufacturer.

Output voltage bottom grade

V_OL is the power provided to be regarded as a 0 logical at exit. The maximum value is indicated by the manufacturer.

Currents

Courant of entry high level

I_IH is the current one crossing the entry when a tension of high level is applied.

Courant of entry bottom grade

I_IL is the current one crossing the entry when a tension of bottom grade is applied.

Courant of exit high level

I_OH is the current one crossing the exit when a power of high level is provided.

Courant of entry bottom grade

I_OL is the current one crossing the exit when a power of bottom grade is provided.

Fan-out or load factor

The fan-out or load factor is the maximum number of entries of other logical integrated circuits which can be controlled by the exit.

Delays of propagation

The signal crossing the integrated circuit is always delayed by:

boarding time t_PLH at the time of a transition from zero logic towards the one logical;
the time of descent t_PHL at the time of a transition from logic towards zero logic.

The product speed-consumption

The product of the delay of propagation and the power of consumption is an indication of performance of the circuit.

Immunity with the noise

The magnetic electric fields and of the environment can induce interfering signals, immunity with the noise is the capacity of an integrated circuit to tolerate the interfering signals.

Logic with injection and absorption of current

Technology differentiates the integrated circuits which provide or absorb a running.

Scale of integration

The scale of integration definite the number of doors contained in the case of the Integrated circuit.

Technologies

TTL

Technology TTL ( Transistor Transistor Logic ) uses mainly junction transistors.

The circuits of technology TTL are generally prefixed by figure 74 (54 on the military and industrial series). This figure is followed of one or more letters representing the family (absence of letter for the standard family), then a code with 2,3 even 4 digits representing the model of the circuit (the fulfilled function).

The various families are the following ones:

TTL: standard series
TTL-L (low power): series with low fuel consumption
TTL-S (shottky): fast series (use of diodes schottky)
TTL-AS (advanced shottky): version improved of the series S
TTL-LS (low power shottky): combination of technologies L and S, it is the most widespread family
TTL-ALS (advanced low power shottky): version improved of the series ACE
TTL-F (FAST: Fairchild Advanced Schottky Technology)
TTL-AF (advanced FAST): version improved of the series F
TTL-HC (high speed C-MOS): It does not act any more technology TTL but of technology C-MOS
TTL-HCT (high speed C-MOS): series HC equipped with logical levels compatible TTL

ECL

Technology ECL (Emitter Common Logic: Logic with common transmitters) was only technology a long time making it possible to reach high frequencies of operation (higher than 100 MHz)

CMOS

Technology complementary metal oxyd semi conductor uses mainly field-effect transistors CMOS.

Hybrid

There exists of numerous hybrid technologies between TTL and CMOS and each year of news are invented.

See too

Fan-out
Table of numerical Karnaugh
Integrated circuit
Electronic

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